The invention relates to an air conditioner for cooling electrical parts. More and more significance attaches to the problem of cooling such components, particularly electric components, given their technical development, since one strives to accommodate as many such components as possible, particularly electronic "intelligence", on the smallest space possible. Therefore, particularly when a plurality of individual devices have been combined in one housing, an attempt has been made to remove the arising heat with the assistance of aeration aggregates. Thereby, the disadvantage of jeopardizing the electrical components, particularly of electronics, due to the dirt drawn in by the aeration air derives. The resolution attempted in contrast thereto by means of cabinets and housings executed dust-tight fails in that, thus, even the slightest air exchange between the inside and outside is interrputed, so that even slight leakage power per unit to be cooled generates an inadmissible inside temperature in the housing. Further, heat exchanger systems have been provided in which the air heated by the electronics or the like within the housing surrounding the electronics is blown by ventilators past an extremely large air exchange surface which emits the heat to a liquid circulation. The warm liquid is conveyed toward the outside to a correspondingly large exchange surface outside of the housing or, respectively, cabinet and is emitted there to the ambient air with the assistance of ventilators. Here, one can only work with a positive temperature drop relative to the outside air. That means that the inside temperature in the cabinet with the electronics or the like must always be higher than the ambient temperature. When, then, the ambient temperature rises above a certain value, then such a heat exchange can no longer be employed. Finally, air conditioners according to the preamble of claim 1 are known. They all share the serious disadvantage that they provide coolers consisting of fine-meshed gilled or ribbed tubes. They are, therefore, unsuited for cooling with dirty air, since this would very rapidly result in the disintegrating of the gilled or ribbed tubes. In order to avoid this disadvantage, filter meshes have been introduced. However, experience has shown that these filter meshes are not changed by the user or are changed too late. This results in disruptions both of the air conditioner as well as of the system which it is meant to cool. A further disadvantage consisted therein that air laced with dirt also flowed around the compressor with all auxiliary and control elements, these then becoming correspondingly dirty or respectively, covered with dust. A further disadvantage of the known air conditioners lies therein that the diversion of the water condensation forming in the space to be cooled ensued toward the outside through a normal plastic hose and, thus, the problem arose for the user as to how he should eliminate this waste water. Finally, it should be pointed out that, given employment of standard components of air-conditioning, a device shape thereby derives which is not necessarily user-compatible, namely, a cubic device shape. A structural shape which is as flat as possible is, however, desirable for attachment to switch cabinets.
In contrast thereto, the object of the invention principally lies therein of designing an air conditioner according to the preamble of claim 1 to such effect that no danger of contamination of parts sensitive to dirt arises.
Due to the separation of the device into two areas protected against air passage, all components, including the compressor, sensitive to dirt and dust are accommodated in the dirt-free first area. The components, particularly the condenser, situated in the second area and, thus, in the stream of dirty air, can be designed without further ado in such manner that they are insensitive to dirt and such that no parts filtering off the dirt, such as ribs, tubes or filter meshes, are required. Thus, an inventive device can also be employed given extremely dirty ambient air. Further, it is functional both given low as well as, specifically, given high ambient temperatures, since the temperatures in the inside of the cabinet exhibiting the electrical components to be cooled is lower than, or, respectively, the same as the ambient temperature. At first, it seems nonsensical per se to also provide the heat-generating compressor in the air stream which is situated in the first area, and, thus, must be cold for cooling the electrical components and the like. Among other things, however, the resolution of the inventive object is achieved by means of disposing the compressor in said first area, accepting a heating of its air stream.
One of the features effects a metered feed of dust-free air to the compressor.
One of the features includes a design of the heat exchange surface of the condenser which is particularly dust-insensitive and easy to clean.
A structurally simple arrangement consisting of tube coils and heat exchange surfaces which produces good thermal contact is achieved by another feature;
Further features prevent water condensation which can have a destructive effect, particularly on sensitive electronic components, from suddenly occurring due to too low a temperature given by unintentional opening of the cabinet containing the electrical components.
Another feature includes the second area coming into consideration for contamination being exploited in order to distribute the water condensation ("liquid dirt") forming in the first area, whereby it is evaporated and, thus, eliminated.
An inventive air conditioner, thus, also resolves the water condensation problem. By means of a control-oriented protection, it prevents the electronics or the like built into the cabinet from being fogged with moisture. Further advantageous are a relatively low weight, as attractive as possible a design, and a selling price suited to the marketplace.
Finally, it should be mentioned that an inventive device is suitable both as original equipment as well as for re-equipping switch cabinets. It can be designed as a plug-in unit. The components provided in the inventive air conditioner are essentially maintenance-free and long-lived.
Further advantages and features of the invention can be derived from the further subclaims, as well as from the following description and the appertaining drawing of an inventive sample embodiment. Shown in the drawing are: